Incandescent lamp socket



June 1, 1937. w. c. TREGONING 2,082,369

INCANDESCENT LAMP SOCKET Filed May 16, 1954 INVENTOR @Q? M,M

' direct connection \50 ed signs using electric '.55' socket provided with my invention,

Patented June 1, 1937 INCANDESCENT LAMP SOCKET William C. Tregoning, Greensburg, Pa.,

to Porcelier Manufacturing Company,

assignor Greensburg, Pa., a corporation of Pennsylvania Application filed May 16, 1934, Serial No. 725,924

5 Claims.

This invention relates to incandescent lamp sockets and, more particularly, to lamp sockets of the type having a porcelain or ceramic body with means at the back end of the socket for to electric wires.

Certain illuminating installations require the use of a number of electric lamp sockets connected in parallel. This is quite true of many types of electric signs. Electric sockets having '10 a ceramicbody are commonly used in installations ofthis character. At the back of the body are parallel recesses adapted to receive parallel electric wires. In these parallel grooves or recesses are connecting screws, by means of which the electric contact elements of the socket can be connected to the wires. The wires are commonly stripped of the insulation at the point where the wires traverse the screws so that the screws need merely be loosened and the wires slipped underthe edge of the screws in order to make the electrical connection. In other words, thewires commonly pass continuously across the end of the socket and do not terminate at the connection screws.

For protection against short circuiting and damage resulting therefrom, it is required that the ends of the sockets be provided with an insulating guard over the connecting screws. Heretofore the socket has commonly been provided with a threaded post at the back end thereof onto which a porcelain cap can be screwed. When the cap is screwed home, it covers the end of the socket" and prevents the wires which traverse the groove from getting out of place, even if the screws should become loosened.

According to the present invention there is provided a guard arrangement for this end of the socket to protect the connecting screws and retain the wires in place, wherein a much more simple form. of guard is provided, the resulting socket being much cheaper to manufacture, much more convenient to use and, in addition to these features, the. overall height of the socket, together with the guard is very materially less than that of sockets heretofore made, with the result that the socket can be much more readily used in places where the depth or" the space for the sockets is very limited. This conservation of space is quite important, particularly in illuminatbulbs. The invention may be readily understood by reference to the accompanying drawing, in

which- Figure 1 is an elevation of the rear end of a showing the guard in the normal position for covering the connecting screws and retaining the electric wires in place;

Figure 2 is a similar view showing the guard moved to its open position;

Figure 3 is a side elevation of the socket showing the guard in closed position;

Figure 4 is a. transverse vertical section in the plane of line IV--IV of Figure 1; and

Figure 5 is a perspective view showing the guard detached from the socket.

In the drawing, 2 designates the main body portion of the socket. This body is commonly formed of porcelain or other ceramic material, but it may, of course, be made of any suitable insulating material. The body 2 is provided with a central recess and in this recess is secured a threaded metal shell 4 for the reception of the base of an incandescent lamp bulb. I have shown the body of the socket as being of twopiece construction, there being a removable end portion 5 which screws onto the outside of the threaded shell 4, this general arrangement being common in the art and forming no part of the present invention. The outside of the base of the body is provided with two transverse parallel grooves 6 and 1. Midway beween the end of each groove is a raised portion 8. Passing through each of these raised portions 8 is an internally threaded eyelet 9. A connecting screw or bolt I0 is threaded into the eyelets 9. One of the eyelets 9 is connected to a base flange portion 4 on the threaded shell 4, while the other eyelet is connected to and secures in place a spring contact member II, the contact member II having a central circular portion l2.

In the base of the recess 3 is a central well 30.. At the bottom of this well and extending through the central portion I3 between the two grooves 6 and I is an eyelet [4. The inner end of this eyelet is bent over on the inside of the well. The other end of the eyelet passes through a guard member l5, this guard member comprising a strip of insulating material. It may be formed of a heavy, dense fiber board of the type commonly used for insulating purposes, or of synthetic resinous materials similar to those sold under the trade names of Bakelite and Micarta. The outer end of this eyelet I4 is flanged over the top of the guard strip so that the guard strip is tightly held against the end of the socket. The eyelet not only provides a holding means for retaining the guard strip in place, but provides a pivot about which the guard l5 can be rotated from an open position shown in Figure 2 to the,

' electric socket.

closed position shown in Figures 1, 3 and 4. The outside flange at one side of the base of the socket along the groove 6 is designated 21%, and the similar flange along the groove 1 is designated 2b. The top of these flanges is flush with the top of the central portion l3 of the base of the socket so that when the guard I5 is in the closed position as shown in Figures 1, 3 and 4, the ends of the guard rest on the tops of the parts 2a and 22), while the center of the guard is supported on the portion l3.

In this position, the guard covers the ends of the screws, extending crosswise or. transversely of the grooves 6 and 1. It thereby prevents anything from coming in contact with the connecting screws I and prevents the wires (not shown) from getting out of the grooves in the event that one of the screws should become loosened. The width of the guard is such that when the guard is turned about the eyelet M as a pivot so that the major axis of the guard is parallel with the grooves, the guard will lie between the two grooves 6 and I. In order to facilitate access to the screws I!) when the guard is in this open position, as shown in Figure 2, the guard is provided with central notched portions |a whereby when the guard is open the ends of the screws are completely exposed and full access can be had thereto.

The eyelet is set so tightly that the guard l5 can only be rotated with difficulty, as it is not desired that the guard shall be rotated freely. In order to further guarantee against free rotation of the guard and its accidental movement to openposition the portion 2a is provided with a small integral spur or point I! which projects very slightly above the plane of the end of the portion 2a. The guard I5 is provided at diagonally opposite corners with holes l8. When the guard is rotated from the position shown in Figure 2 in either direction to the closed position shown in Figure 1, the end of the guard will be sprung up over the spur or point I1 and when the guard is in the right position the spur will enter one of the holes l8 of the guard and lock the guard against rotation. Thereafter, the guard can only be opened by springing out the end of the guard until the point I! is clear of the opening l8.

It is the practice to assemble the socket with the guard in the open position shown in Figure 2. It is shipped in this way from the factory. After the socket has been installed and the connections have been completed, the guard is rotated to the closed position. Thereafter until the socket is to be removed, there is no need to disturb the guard.

While the top of the metal eyelet I4 is exposed where it is peened over the guard strip IS, the inner end of this eyelet is in the well 3a and, therefore, positioned so that it cannot contact with any of the metallic elements inside the By reason of the contact l2 being of circular shape and having a large opening at its center, this central contact cannot possibly be forced down into the well 3a.

The setting of the eyelet M to secure the guard [5 in place is an extremely simple and easy operation to perform. The eyelet itself is inexpensive, and the guard can be blanked out of sheets of insulating material at a very small cost. The arrangement is, therefore, much more simple and economical than sockets of the same type as heretofore constructed. Moreover, the formation of the grooves and recesses for accommodating the screws I0 is more simple with the present invention due to the different manner of supporting the guard by simplifying the molding of the ceramic material. A saving in ceramic material is effected also by reason of the difierence in the manner of supporting the guard. The guard, once it has been set in closed position, cannot be freely roated and, therefore, cannot become accidentally displaced. Moreover, the guard is of considerably less thickness than the guards heretofore provided in sockets of the same type,

resulting in the reduction in the overall height of the socket.

While I have specifically described a particular embodiment of my invention, it will be understood that changes may be made in the detailed construction within the contemplation of my invention and under the scope of the following claims.

I claim:

1. An electric socket comprising a socket element with a base member having parallel wire receiving channels in the end thereof at opposite sides of the center thereof with wire-connecting terminals therein, and a guard member pivotally secured to the end of the base member at substantially the center thereof, said member being of a shape different from the shape of the end of the base member on which it is mounted, said member being movable from a position where it lies between the two channels to a position where it lies crosswise of the two channels, the guard member having a length in excess of its width, said guard member being of insulating material and being entirely free of electrical contacts.

2. A lamp socket comprising a circular base member of ceramic material having a high central portion at the back thereof and having a high upright portion at diametrically opposite sides of the central portion, connector screws in the recesses between the high central portion and said diametrically opposite high portions, said connector screws being diametrically opposite each other, a non-circular guard member of insulating material, means passing through said central portion of the base and through the guard member between its ends for pivotally securing the guard member to the end'of the base, said guard member being movable in a plane transverse to the axis of the pivotfrom a position where it exposes such screws and lies between them to a position where it covers said screws.

3. A lamp socket comprising a base member of ceramic material having a high central portion at the back thereof and having a high upright portion at diametrically opposite sides of the central portion, connectorscrews in the recesses between the high central portion and said diametrically opposite high portions, said connector screws being diametrically opposite each other, a thin stiff guard member of insulating material, means passing through said central portion of the base and through the guard mem-- ber and being riveted over against the guard member for pivotally seeming the guard member to the end of the base, said guard member being movable in a plane parallel with the plane of the end of the base member from a position where it exposes such screws to a position where it covers said screws, and interlocking means on the guard member and the base member for holding the guard member against free rotation When it is in position over the screws, said guard member being free to turn when wires are engaged in the recesses between said central and upright portions of the base.

A lamp socket comprising a base member of ceramic material having a high central portion at the back thereof and having a high upright portion at diametrically opposite sides of the central portion, connector screws in the recesses between the high central portion and said diametrically opposite high portions, said connector screws being diametrically opposite each other, a guard member of insulating material, means passing through said central portion of the base for pivotally securing the guard member to the end of the base, said guard member being movable from a position Where it exposes such screws to a position where it covers said screws, and interlocking means on the guard member and the base member for holding the guard member against free rotation when it is in position over the screw said interlocking means comprising a spur projecting from the end of one of said diametrically opposite high portions, the guard member having an opening to receive the spur.

5. An electric socket of the class described comprising a base member of insulating material having parallel wire receiving grooves at the end thereof and having contact screws in said grooves, a guard member over said grooves having a length greater than its width and being of a width about equal to the distance between the grooves and movable in a plane from an open position where the screws are exposed to a closed position where the screws are covered by the guard member, means passing through that portion of the base member between the two grooves for securing the guard member in place, said means being insulated from any of the metal parts of the socket, and detent means utilizing the inherent resilience of the guard member for restraining the guard against free rotation when it is in closed position.

WILLIAM C. TREGONING. 

